4ms制备大面积多孔石墨烯，用于可穿戴多功能健康监测系统

摘要：由于现代人对健康的关注与日俱增，可穿戴健康监测系统是开启第四次工业革命时代的一个大有可为的设备。一些研究人员已经展示了可穿戴健康监测系统，但仍存在性能低、效率低和制造工艺复杂等关键问题。本文，韩国全北大学Jung Hwan Park、Han Eol Lee等研

1成果简介

由于现代人对健康的关注与日俱增，可穿戴健康监测系统是开启第四次工业革命时代的一个大有可为的设备。一些研究人员已经展示了可穿戴健康监测系统，但仍存在性能低、效率低和制造工艺复杂等关键问题。本文，韩国全北大学Jung Hwan Park、Han Eol Lee等研究人员在《Energy & Environmental Materials》期刊发表名为“Wearable Multifunctional Health Monitoring Systems Enabled by Ultrafast Flash-Induced 3D Porous Graphene”的论文，研究展示了世界上首个基于闪速诱导多孔石墨烯（FPG）的可穿戴多功能健康监测系统。FPG 通过闪光灯高效合成，在4毫秒内即可形成大面积。此外，为了证明多孔石墨烯的传感性能，还在单一基底上制作了一个可穿戴的多功能健康监测系统。利用丝网印刷技术，成功地在凹凸不平的 FPG 表面形成了碳纳米管-聚二甲基硅氧烷（CNT-PDMS）纳米复合电极。三维多孔结构 FPG 的大表面积提高了基于 FPG 的可穿戴多功能健康监测系统的性能。最后，基于 FPG 的可穿戴多功能健康监测系统有效地检测了运动、皮肤温度和汗液，应变 GF 为 2564.38，在皮肤温度范围内的线性热响应为 0.98 Ω°C-1，离子检测限低至 10 μm。

2图文导读

图1、a) Schematic illustration of (i) FPG synthesis, (ii) fabrication process of CNT-PDMS nanocomposite electrode via screen printing, (iii) ionophore drop casting on FPG, and (iv) signal detection mechanism. b) Photographs of pristine PI and FPG on PI film, producing FPG layers with various shapes onto the desired locations. c) Optical image of flexible multifunctional sensor. The inset is a micro-CT image of FPG surface, showing its porous structure.

图2、Fabrication process and structural characterization of FPG. a) Schematic illustration of FPG formation enabled by successive flashlight irradiation, b) Temperature distribution of PI simulated by COMSOL under flash fluence of 10, 18, 22 J cm−2, c) FPG synthesized under flash energy densities of 10, 18, 22 J cm−2, d) SEM images of FPG generated under first (at 14 and 22 J cm−2) and second (at 22 J cm−2) flashlight exposures, e) Porosity of pristine PI, and FPGs synthesized upon first (at 14 and 22 J cm−2) and second (at 22 J cm−2) flash lamp processes. f) Pore size distribution of the optimized FPG obtained by consecutive two shots of flash fluence at 22 J cm−2, g) Quantitative pore size distribution of the optimized FPG (twice exposures at 22 J cm−2).

图3.Physicochemical properties of FPG. a) Sheet resistance of FPG as a function of flash fluence (from 12 to 28 J cm−2), and the number of irradiations (single and double), b) Raman spectra of FPG formed by single and twice exposure of flashlight with the energy density of 22 J cm−2. Inset shows ID/IG ratio of the corresponding FPGs, c) XPS spectra of pristine PI, and FPG processed by single and double exposure of flashlight with 22 J cm−2 fluence, d) FT-IR spectra of pristine PI, and FPG upon first and second (at 22 J cm−2) flash lamp processes.

图4、a) 3D illustration (left) and photograph (right) and of screen printing process for manufacturing nanocomposite-based electrodes. b) Resistance of CNT-PDMS nanocomposite ink with various CNT concentrations. c) Storage modulus and loss modulus of 3 wt% CNT-PDMS nanocomposite ink. d) Printability of screen printed electrodes at different printing speeds. e) Viscosity of 3 wt% CNT-PDMS nanocomposite ink at different shear rates.

图5、a) Resistance change of FPG-based strain sensor under bent. b) Resistance of FPG-based temperature sensor. The inset shows the resistance of the device in the range of typical human body temperature. Potentiometric response of c) K and d) Cl+− ion sensor in the successive concentration range of KCl solution from 10−5 to 1 m.

图6、a) Optical image of FPG-based multifunctional sensor, attached to the human finger. Strain sensing characteristics under b) vertical strain and c) horizontal strain of human finger. d) Measurement setup images for monitoring body movements and skin temperature through our FPG-based multifunctional sensor. e) Resistance changes of FPG-based strain sensor by flat (push-up) and bending state (push-down) of the human scapula. f) Real-time skin temperature monitoring by FPG-based temperature sensor during workout, comparing to commercial temperature sensor. g) Photographs of the skin-attached multifunctional FPG-based sensor for sweat ion monitoring. The litmus paper color changes before and after exercise, confirming that human perspiration occurred on the skin surface during the exercise. Real-time ion sensing results of the FPG-based h) K and i) Cl+− ion sensors during exercise and relaxation.

3小结

总之，我们利用闪光诱导的简单快速多孔石墨烯制造工艺，展示了一种可穿戴多功能健康监测系统。由于碳化和石墨化作用，在 22 J cm-2 的辐照功率下双枪照射的 FPG 与单枪照射条件下相比，显示出较低的片状电阻和 ID/IG 比。通过优化丝网印刷技术，使用 3 wt% 的 CNT-PDMS 纳米复合油墨和 50 mm s-1 的印刷速度，实现了基于纳米复合材料的电极，克服了三维 FPG 表面粗糙/不平整的问题。基于 FPG 的应变和温度传感器具有卓越的机械稳定性，其 GF 值高达 2564.38，线性热响应为 0.98 Ω°C-1。汗液离子传感器在 10 至 100 μm 的 K 和 Cl+- 浓度范围内具有更强的检测能力，足以监测人体汗液中的离子变化。最后，我们成功地实现了可穿戴多功能健康监测系统，该系统包含应变、温度和汗液离子传感器，可在单个 PI 基底面上分析人体生物信号。在俯卧撑运动中，我们的应变传感器检测到肩胛骨的细微/复杂运动，温度传感器测量到皮肤温度从 29 °C上升到 31 °C。此外，我们的离子传感器还能持续监测运动过程中 K 和 Cl+- 离子浓度的变化，其检测限高达 10 μm。我们相信，FPG可以成为下一代电子材料，应用于生物医学传感器、植物生长监测和电子皮肤等多个工业领域。

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